The present invention relates to electronic device employing a multi-layer display apparatus, in which multiple layers are combined such as liquid crystal display panel layers, and more specifically to electronic device so designed as to combine display states of the multi-layer display panel layers.
Electronic device has been commercialized with more functions than before, such as multifunction digital electronic watches. By featuring more functions, these products are extremely convenient for users. Products combining two layers of upper and lower digital liquid crystal display panels have also been commercialized.
The prior art will first be described with reference to FIGS. 6, 7(a) and 7(b).
FIG. 6 shows one example of a conventional multifunction digital electronic watch. The watch, which combines two layers of upper and lower digital liquid crystal display panel layers, features a calendar function, an alarm function, a world time function, and a timer function. Shown are a date display section 610, a time display section 620, and a day-of-week display section 630.
FIG. 7(a) shows an upper digital liquid crystal display panel layer of the multifunction digital electronic watch in which two layers of upper and lower layers of FIG. 6 are combined, time display segments 710 formed from 7-segment digit columns and AM/PM segments, and day-of-week segments (position) 720.
FIG. 7 (b) shows a lower digital liquid crystal display panel layer of the multifunction digital electronic watch in which two layers of upper and lower layers of FIG. 6 are combined. The digital liquid crystal panel of FIG. 6 is divided into the upper layer digital liquid crystal display panel of Fig. (a) carrying mode symbols for the alarm function, the world time function, and the timer function, and the lower layer digital liquid crystal display panel of Fig. (b) carrying the calendar function. Shown are calendar display segments 730 capable of displaying all the days of one month, month/date display segments 740 combining a month display for indicating what calendar month is shown on the calendar display segments 730 and a date display for indicating the date in a time calendar mode (to be described hereinafter), day-of-week designation segments 750 for displaying a predetermined day of week by masking the other days, a world time mode symbol segment 780, a stopwatch mode symbol segment 790, and a timer mode symbol segment 800.
In the time calendar mode shown in FIG. 6, by driving the digital liquid crystal display panel layers, in which two layers of upper and lower layers are combined, the time, date, and day-of-week are displayed as the current time of xe2x80x9c12 o""clock, 36 minutes, and 48 seconds AMxe2x80x9d on the 7-segment digit columns and the AM/PM segments of the time display segments 710 of FIG. 7(a), the date of xe2x80x9c3xe2x80x9d on the month/date display segments 740, the day-of-week of xe2x80x9cWednesdayxe2x80x9d on the day-of-week display segments 720 and the day-of-week designation segments 750.
However, because the display operations are performed by combining the upper layer and lower layer segments of the upper digital liquid crystal display panel layer shown in FIG. 7(a) and the lower digital liquid crystal display panel layer shown in FIG. 7(b), various functional mode displays, such as the time calendar mode shown in FIG. 6, are performed, and the display control operations for the multifunction digital electronic watch, in which two layers of upper and lower layers are combined, require complex control operations for turning on the upper layer and lower layer segments in combination.
Furthermore, in the upper layer digital liquid crystal display panel shown in FIG. 7(a) and the lower layer digital liquid crystal display panel shown in FIG. 7(b), the 7-segment digits and symbol segments, or only the symbol segments, are provided. Since functional information can only be displayed on the segments provided on the upper layer digital liquid crystal display panel or on the lower layer digital liquid crystal display panel even though the multifunction digital electronic watch has a combination of two layers of upper and lower layers, this configuration cannot flexibly meet the needs of the present day information-oriented society.
Furthermore, after a sudden switch to the next functional mode display during switching of various functional modes, a predetermined mode symbol is turned on among the alarm mode symbol segment 760, the alarm set symbol segment 770, the world time mode symbol segment 780, the stopwatch mode symbol segment 790, or the timer mode symbol segment 800, resulting in an uninteresting display during changes in the functional mode display.
A general TN-type liquid crystal cell has a configuration where two opposing plates of glass attached with an orientation film and a transparent electrode have the orientation of the orientation film twisted by 90 degrees, between which liquid crystal material is injected, and a polarizing plate is affixed to the outer side of each glass with the polarized light axis aligned with the orientation direction of the orientation film.
A liquid crystal molecule has a property of aligning with a plate having fine grooves in a fixed direction, namely, along the orientation direction when in contact with the orientation film. At the liquid crystal layer sandwiched between glass forming the orientation film, the orientation direction of which is shifted by 90 degrees, the liquid crystal molecule is twisted 90 degrees between the top and the bottom. Then, when light passes through the liquid crystal layer, the oscillation plane of the light bends in the direction of the liquid crystal molecule.
Furthermore, the polarizing plates affixed to the outer side of the two plates of glass of the above-mentioned liquid crystal cell use polarizing plates called absorption-type polarizing plates having a polarized light axis that allows light to be transmitted in the fixed oscillation direction and an absorption axis that causes light to be absorbed in an oscillation direction shifted by 90 degrees from the polarized light axis.
In the foregoing configuration, when external light strikes the liquid crystal cell, the light transmitted through one polarizing plate is bent and twisted 90 degrees in the direction of the liquid crystal molecules at the liquid crystal layer at the parts where no voltage is applied to the transparent electrodes provided on the inner surface of each of the two plates of glass, and is transmitted through the other polarizing plate. On the other hand, at the parts where voltage is applied to the transparent electrodes, the liquid crystal molecules align along the direction of the electric field so that the light is not affected by the influence of the liquid crystal molecules and travels straight without twisting of the oscillation plane. When the light reaches the other polarizing plate, the light cannot be transmitted and is absorbed since the polarized light axis of the polarizing plate and the oscillation direction of the light are shifted by 90 degrees.
In the liquid crystal cell of an ordinary watch, by placing a reflecting plate or a semi-transparent reflecting plate under the polarizing plate on the inner side of the watch, the incident light strikes the reflecting plate and returns so as to appear bright at the parts where the voltage of the electrodes arranged on the glass is off, and the incident light is absorbed by the polarizing plate and does not return so as to appear black at the parts where the voltage of the electrodes is on. Thus, by manipulating the voltages of the electrodes formed on the glass and from the combination of shapes of the electrodes above the liquid crystal cell, letters and numerals can be displayed.
Heretofore, besides wristwatches having watch hand displays, many watches performing time display or graphic display operations using liquid crystal cells have been commercialized. However, for watches having only one liquid crystal cell, it was impossible to display different patterns on the same liquid crystal cell display area.
This is because patterns of segments or letters were formed beforehand with transparent electrodes on the single liquid crystal cell. Although it is possible to display different patterns in the same area by using a dot-matrix display, the problem is that the spaces between dots are noticeable and it is impossible to display completely different shapes without the spaces.
Although it may be conceivable to display different patterns in the same area by further overlapping a plurality of liquid crystal cells, conventional liquid crystal cells are usually affixed with absorption-type polarizing plates and the light is attenuated even after passing through two polarizing plates for a watch with one liquid crystal cell, thereby resulting in a dark time display. Therefore, the problem is that the display becomes even darker if two liquid crystal cells are overlapped and difficult to read.
The purpose of the present invention solves the above-mentioned problems by providing electronic device with simple display control of the electronic device in which multiple layers are combined, and based on this, by providing electronic device that takes into consideration the visual effect for bright and easy to read electronic device.
In order to achieve the above-mentioned objects, in an electronic device comprising information generating means for generating information, a display apparatus, and display driving means for outputting display driving signals to the display apparatus on the basis of information from the information generating means, the display apparatus comprises a multi-layer display panel, and when information display is performed on one arbitrary display panel layer among the multi-layer display panel, the display driving means clears all segments of other display panel layers, thereby making it possible to achieve simple display control and effective use of the panel display.
The information generating means comprises reference signal generating means, and means for generating information, such as time information on the basis of the reference signal from the reference signal generating means, the display apparatus comprises a multi-layer display panel, with all or part of at least one layer of the multi-layer display panel having a dot-matrix format, and the display driving means comprises a dot-matrix controller for controlling the display of a dot-matrix display panel to handle a variety of functional mode displays.
If state transition controlling means is provided for performing control of the display transitions of the display apparatus, it is possible to add variations so as to emphasize the transition display for the user.
If the above-mentioned display apparatus is configured so as to comprise a multi-layer liquid crystal display panel in which liquid crystal display cells are arranged in multiple layers, display can be varied and the power consumption can be reduced.
If a reflecting-type polarizing plate is used for at least one liquid crystal display cell of the above-mentioned display apparatus, it is possible to realize a brighter display having richer variations.
If the above-mentioned display apparatus is a multi-layer liquid crystal display panel in which a plurality of liquid crystal display cells are arranged so as to overlap and the lowest layer liquid crystal cell comprises a reflecting-type polarizing plate that opposes a backface member, it is possible to realize a brighter display having richer variations.
If the above-mentioned display apparatus is provided with a plurality of liquid crystal display cells arranged so as to overlap, and a light diffusion layer between the above-mentioned backface member arranged on the lowest layer side of the multi-layer liquid crystal display panel and the above-mentioned lowest layer liquid crystal display cell, it is possible to realize a bright and consistent display.
If at least one polarizing plate, besides the reflecting-type polarizing plate of the lowest layer liquid crystal display cell, is a reflecting-type polarizing plate, the application of the reflecting-type polarizing plate can result in a brighter display.
If the above-mentioned liquid crystal display panel comprises two layers of liquid crystal cells, and three polarizing plates of which the uppermost layer polarizing plate is an absorption-type polarizing plate and the middle layer polarizing plate is a reflecting-type polarizing plate, it is possible to realize a display rich in variations.
If the surface of the above-mentioned backface member is colored, it is possible to have a display rich in variations.
If the above-mentioned backface member is a reflecting plate or an EL plate, a bright display can be achieved.
If the above-mentioned multi-layer display panel has a quadrilateral display screen, of which only the central area is a dot-matrix format display, variety can be added to the display.
If the above-mentioned middle layer reflecting-type polarizing plate is affixed to an upper layer liquid crystal cell and separated from a lower layer liquid crystal cell, the polarizing plate can serve a dual purpose.
If the display of the above-mentioned liquid crystal panel is set to a reflecting state when no voltage is applied to the above-mentioned upper layer liquid crystal cell, an appearance rich in variations can be obtained.
If the display of the above-mentioned liquid crystal panel is set to a reflecting state when a voltage is applied to the above-mentioned upper layer liquid crystal cell, an appearance rich in variations can be obtained.